Stop for telescoping members



May 25, 1937.

J. J. O'NEILL STOP FOR TELESCOPING MEMBERS Filed Aug. 26, 1935 INVENTOR Jams; Z OWE/Z1 ATTORNEY Patented May 25, 1937 UNITED STATES PATENT OFFICE 1 Claim.

This invention relates to devices used to prevent relative movement between telescoping members such as the sections of microphone stands or the like.

It is an object of the invention to provide a frictional device of the character described which will not mar the surface in which it is in contact.

Another object of the invention is to provide a device of the character referred to which is possessed of unusual gripping power.

Still another object of the invention is to provide a stop for the use described which is extremely simple in construction, easily made, and not readily injured by rough usage.

Referring to the drawing:

Figure 1 is a top plan view of the stop of my invention shown applied to a tubular member which is shown in section.

Figure 2 is a side elevational view of the stop in position on one of a pair of telescoped tubular members.

In detail the stop of my invention comprises a length of spring wire, of rectangular cross-section, bent to provide crossed portions and an intermediate expandible loop, the portions of the wire forming\ the loop, as shown in Figure 2, being offset so as to lie in helical relationship about a cylindrical object, such as the tubular member 4 illustrated in the drawing.

The end portions of the wire extend radially from the loop contiguously to the crossed portions and divergently with respect to each other, and are again bent so that the extremity of each end portion will overlie the projecting portion of the wire to provide finger grips 6. It will be observed that the finger grips lie in approximately the same plane, i. e. they are formed symmetrically about a plane passing horizontally through the device, and that the relation of the handles with respect to the loop is such that the crossed portions normally close the loop.

In use, the stop may be slipped over the tubular member 4 by squeezing the grips 6 together with the fingers which will increase the opening of the loop 3 sufficiently to allow insertion of the member whereupon release of the pressure on the grips will allow the loop to contract, due to the resilient nature of the wire, and grip the member. Thus, if a telescoping member, such as the tube 1 shown about the member 4 be applied to the latter, the stop will prevent relative movement therebetween in one direction.

It will be noted that the looped portion 3 of the stop completely encircles the tube to which it is applied and that the entire inner surface of the loop is in contact with the periphery of the tube. This latter feature is accomplished by twisting the wire as it is bent about the forming mandrel so that the surface of the wire facing the periphery of the mandrel is maintained tangent thereto. If this twisting was not included in the formation of the stop the surface of the wire would not be parallel with the axis of the cylindrical member with which the stop is to be used with the result that when the stop was applied the sharp edges of the wire would bite into and mar the surface, or finish, of the member.

The stop of my invention may be applied to any device in which stops of this character are used without the danger of marring or scratching even lightly oxidized surfaces, this being due to the particular construction employed in the manufacture of the stop in insuring that the inner surface of the loop is truly cylindrical and devoid of any projecting edges which would mar the surfaces on which it is mounted.

Another feature which assists in preventing marring of the surfaces referred to is the fact that the grips 6 are disposed, as was mentioned above, in a horizontal plane passing through the stop. Since the grips are so positioned it is obvious that, when pressure is applied to bring the grips together, there will be no tendency, which would be the case if the grips were ofiset from the plane mentioned, to cause rocking of the stop in the direction of the axis of the tube 4 thereby preventing the sharp edges of the wire from cutting into the surface of the tube.

While I have described the stop of my invention as being composed of wire of rectangular cross section, it is obvious that half round wire, or wire having any other cross sectional formation as long as it has a flat surface for engagement with the object upon which it is mounted, may be used without departing from the spirit of the invention.

I claim:

A stop for limiting relative movement of two movable members of different diameters, one of which encircles and is slidable over the other, said stop consisting of a length of spring wire having crossed portions and an intermediate expandible loop adapted to encircle and grip the smaller member, the end portions of said wire extending radially from the loop contiguously to the crossed portions and serving as means for adjusting the stop on the smaller member, the inner surface of the loop being fiat and engageable with said smaller telescoping member, the wire forming the device having a torsional twist therein so disposed as to maintain the axial flat surface of the loop parallel with the axis thereof so as to substantially resist slidable movement under the influence of axially applied forces imparted thereto.

JAMES J. O'NEILL. 

